1. Field of the Invention
The invention relates to a plate-type heat exchanger having a plate block or a stack of partition plates, which delimit flow channel layers between them. In other words, the partition plates serve as fluid-separating walls between successive flow channel layers in the stack direction. These successive flow channel layers usually comprise two or more different liquid or gaseous heat transfer media which are to be brought into thermal contact with one another. The heat transfer media usually flows through the channels in an alternating manner. The partition plates, preferably, have a good thermal conductivity.
2. Description of Related Art
A plate-type heat exchanger is described in commonly asssigned, earlier German patent application 199 09 881. The crosscurrent-type heat exchanger described therein includes partition plates, into which shaped-out moldings are formed. Regions of the partition plates in the plate block are in contact with adjacent partition plates by means of the shaped-out moldings, In each instance, adjacent partition plates are spaced apart by the shaped-out molding regions and thereby form the boundaries for a flow channel layer, in the stack direction, between the partition plates. In side regions, the partition plates are provided with inlet-channel and outlet-channel apertures. Through the aligned overlap of these apertures on the edge side of the stack, manifold channels which open out at the end sides of the stack are formed. These manifold channels serve the purpose of distributing the respective heat-transfer medium to the corresponding flow channel layers and for collecting the heat-transfer medium which leaves the flow channel layers.
The documents DE 197 07 648 A1 and DE 198 15 218 A1 have described plate-type heat exchangers. The stacked structure of these heat exchangers includes flat plates of different types. Specifically, these flow channel plates include plates which are provided with apertures which form flow channels, as well as partitioning intermediate plates which are arranged alternately with the flow channel plates in the stack and serve as partitions for the flow channels of the flow channel plates. Depending on the particular embodiment, lateral manifold apertures which overlap one another in an aligned manner in the stack are made in all the plates. This forms corresponding manifold channels which open out at the end sides of the stack. Alternatively, the flow channels of the flow channel plates, in both end regions, extend beyond the intermediate or partition plates. As a result, a connection structure is formed, in which the relevant heat-transfer medium can be fed laterally to the stack and removed therefrom. In the process, on the relevant stack sides of the intermediate plate planes, the heat transfer medium passes into the protruding flow channels of the flow channels plates and, in a corresponding manner, passes out of them again.
In accomplishing the objects of the invention, there has been provided according to one aspect of the invention a plate heat exchanger comprising a plurality of partition plates arranged (i) to form a plate block or a plate stack and (ii) to delimit, in alternating directions, layers of flow channels between adjacent partition plates within said plurality of partition plates; wherein a first partition plate comprises (a) a first main side; (b) a second main side; (c) a first solid or folded edge which projects out of the plane of at least one of said main sides; and (d) a second solid or folded edge, opposite said first solid or folded edge, which projects out of the plane of the same main side as and in the same direction as said first solid or folded edge; a second partition plate joined to said first partition plate in a fluid-tight manner along said first and second solid or folded edges and spaced apart from said first partition plate by said first and said second solid or folded edges, thereby defining a flow channel layer between said first partition plate and said second partition plate.
According to another aspect of the invention, there is provided a plate heat exchanger comprising a plurality of partition plates arranged in a stack, wherein each partition plate comprises (a) a center portion; (b) a first edge region having a thickness greater than a thickness of said center portion; and (c) a second edge region, opposite said first edge region, having a thickness greater than a thickness of said center portion; and wherein each plate is joined to an adjacent plate along said first edge region and said second edge region thereby defining a flow channel between each plate and an adjacent plate; and wherein successive plates within said stack are arranged at an angle of 90xc2x0 relative to a previous partition plate thereby defining flow channels in a first direction and a second direction.
Further objects, features and advantages of the present invention will become apparent from the detailed description of preferred embodiments that follows when considered together with the accompanying drawings.